38 ROMANCE OF THE INSECT WORLD CHAP. 



inclusive of the bees (Hymenoptera) constitute a 

 little world by themselves, but though their numbers 

 are enormous, all alike are guided by the same general 

 habits and instincts. Few insects, if any, are exempt 

 from their attacks. Usually the female seeks out a 

 caterpillar, a larva, or insect suited to her purpose, 

 and lays her eggs in or on its body, and the larvae 

 that are born of these eggs feed upon the fatty tissues 

 of their host, leaving its vital organs for a time unin- 

 jured, for were the host to die the parasites could not 

 survive. The internal parts of the victim are not de- 

 voured until the parasitic larvae are nearly full-grown 

 and fed, and ready to change into pupae, when a pro- 

 longation of the life of the unfortunate creature is un- 

 necessary. In some cases the victim, should it be a 

 caterpillar, continues to feed and live as though nothing 

 were amiss subsequent to its reception of its unwel- 

 come guests. It may even manage to turn to chrysalis; 

 but it never attains to the perfect form, when it could 

 lay eggs and reproduce its kind, because invariably ere 

 it reaches the final stage the maturing larvae it con- 

 tains have destroyed it, by a slow but sure consump- 

 tion. Thus it often happens to a butterfly collector 

 who has been looking forward to see a fine butterfly 

 emerge from its chrysalis, to be disappointed, and to 

 feel chagrin, by the appearance of several little parasitic 

 Hymenoptera,* which, unknown to him, the butterfly 

 has all along been sustaining, and to whom it has at 

 last been compelled to yield up its life. 



When a parasite in open day finds an insect that 

 will answer admirably as the nourishment for her 

 future larvae, and deposits an egg in it, the act does 



